e360 digest

Reducing the emissions of four critical pollutants in the coming decades could at least temporarily slow the rate of global warming and reduce projected sea level rise by as much as 50 percent, according to a new study. Building on previous research that found that reducing the emissions of four short-lived pollutants — tropospheric ozone, hydrofluorocarbons, black carbon, and methane — could slow the rate of global warming by 50 percent, the new study projects that sea-level rise could, in turn, be reduced by 24 to 50 percent by 2100, depending on the level of emissions cuts. Unlike carbon dioxide, which persists in the atmosphere for centuries, these four pollutants remain in the atmosphere anywhere from a week to a decade, so altering their atmospheric concentrations can have a more immediate effect on the global climate, scientists say. “Society can significantly reduce the threat to coastal cities if it moves quickly on a handful of pollutants,” said Aixue Hu, a researcher at the National Center for Atmospheric Research (NCAR) and lead author of the study published in the journal Nature Climate Change.